First setting foot in the upper world,

上界, the upper world — everything above the mortal one. The poem starts at the threshold and works inwards.

all at once he entered the halls of Heaven.

天堂 here is architecture, not theology: the halls of Heaven, the Jade Emperor's court, a place with doors and staff. Modern Chinese uses the same two characters for the paradise of the afterlife, which is not what is meant.

Ten thousand shafts of golden light came tumbling through rose-red rainbows,

紅霓 is the red-edged rainbow. This kind of long descriptive set piece is called a 賦, and it opens by soaking the whole scene in coloured light.

a thousand strands of auspicious vapor breathed out into purple mist.

瑞氣, "lucky vapour," and 紫霧, "purple mist," are the standard signals that something holy is present — visual shorthand a Ming reader caught instantly. Purple belongs to emperors and to heavens alike.

He looked upon the Southern Gate of Heaven:

南天門, the Southern Gate — the very door he was standing outside a page ago. 那 is nà, "that," pointing at it.

deep blue-green, all wrought of glazed lapis;

琉璃 is glazed lapis, or coloured glass; the novel reserves it for buildings in Heaven.

bright and dazzling, fashioned of precious jade.

粧成 (the older way of writing 妝成) is the verb for making up a face or dressing a person. The gate is not built. It is dressed.

On either hand stood ranks of dozens of Heaven-quelling marshals — each propping the ridge-beams and leaning on the pillars, gripping bright blades and holding plumed standards;

鎮天元帥 are the marshals who garrison Heaven. 銑 (here xiǎn) is a bright ceremonial blade and 旄 (máo) a yak-tail standard — parade gear that says "command" rather than "combat." The run is long, and the edition keeps it unbroken so the whole rank sweeps past in one breath.

below were arrayed a dozen or more warriors in golden mail — each bearing pike and hanging whip, gripping saber and brandishing sword.

金甲神人, divine warriors in golden armour. Marshals on the gallery, troops on the floor: the two lines are built as a matched pair, which is how this entire poem works.

The outer courts were striking enough;

外廂, the outer quarter, against 入內, going in. This is the hinge — the eye stops looking at the gate and walks through it.

but within, the sight astonished:

And the inside beats the outside. The tour keeps moving.

along the inner walls rose great pillars, coiled about with sun-bright, scarlet-bearded dragons of golden scale;

赤鬚龍, the scarlet-whiskered golden dragon wound round the pillars. Dragons on columns are standard imperial decoration; here somebody has turned the volume up.

and there were long bridges, on which wheeled and circled rainbow-plumed, crimson-crested phoenixes soaring into the void.

丹頂鳳, the red-crested phoenix. Dragon on the pillar, phoenix on the bridge — another matched pair.

Bright wisps of cloud-glow lit the heavenly light,

明霞, bright glow on cloud. The description lifts off the buildings and into the air.

blue-green mists hung dense and veiled the Dipper's mouth.

斗口 is the "mouth" of the Northern Dipper, 北斗 — the open end of the ladle. The mist up here is thick enough to hide a constellation.

In this Heaven there are thirty-three celestial palaces — the Cloud-Dispatch Palace, the Vaiśravaṇa Palace, the Five-Brightness Palace, the Sun Palace, the Flower-Joy Palace, and the rest — each palace-ridge crowned with a beast of molten gold;

The 三十三 is not a round number picked at random: it echoes the Buddhist heaven of the thirty-three, Trāyastriṃśa, 忉利天, and 毘沙宮 is named for Vaiśravaṇa. Buddhist furniture inside a Daoist court is exactly how this novel builds. The row of dots marks a list the original itself cuts short, and a 穩獸 is one of those guardian-beasts that sit in a line along a Chinese roof-ridge.

and there are seventy-two tiers of treasure-halls — the Court-Assembly Hall, the Void-Transcending Hall, the Jeweled-Radiance Hall, the Heavenly Kings' Hall, the Numinous Officers' Hall, and the rest — each colonnade ranged with jade qilin.

七十二重寶殿, seventy-two tiers of halls, answer the thirty-three palaces, with another list cut short the same way, and a jade 麒麟 — the auspicious beast usually called a qilin — set along every colonnade.

On the Terrace of the Star of Longevity bloom famed flowers that for a thousand thousand years never fade;

壽星臺, the terrace of the Star of Longevity: the high-domed, white-bearded god of long life who still turns up on birthday cakes and buns. In 不卸 the 不 becomes bú before the falling tone of 卸.

by the elixir-refining furnace grow embroidered grasses that through ten thousand ages stay ever green.

煉藥爐, the furnace where elixirs are refined. Keep an eye on this equipment: Wukong will be back at it, and it will not go well for anyone.

Coming again before the Tower of Sacred Audience:

朝聖樓, the Tower of Sacred Audience. 又至那, "and coming again to —," is a stage direction moving the tour along; the edition keeps it whole rather than splitting it off.

crimson gauze robes, their constellations ablaze;

絳紗衣, crimson gauze robes with constellations worked into them: what the assembled immortals wear.

lotus-blossom caps, their gold and jade resplendent.

芙蓉冠, the lotus cap that goes with the robe. Between them, two lines dress an entire congregation.

Jade hairpins and pearl-sewn slippers,

玉簪珠履 and 紫綬金章 — jade hairpins, pearl-sewn slippers, purple seal-cords, gold insignia. This is not jewellery, it is uniform: rank you can read from across a hall.

purple seal-cords and golden insignia.

The second half of a four-and-four pairing, ornament matched to office.

When the golden bell is struck, the spirits' memorials of the Three Bureaus ascend the vermilion steps;

三曹, the Three Bureaus — Heaven, Earth and Water, the standard Daoist trio — and 丹墀, the vermilion stair below the throne where petitions are handed up. The paperwork goes up the steps. Nothing here happens without a document.

when the heavenly drum sounds, the myriad sages pay court and attend upon the Jade Emperor.

參 is cān, to attend an audience and pay homage. In 朝王 the 朝 is cháo, "to hold or attend court," not zhāo, "morning." Bell, drum, and the whole sky files in.

Coming again to the Hall of Numinous Mists:

靈霄寶殿, the Hall of Numinous Mists: the Jade Emperor's throne room and the centre of everything. Wukong will threaten to smash his way into it twice before the chapter is over.

golden studs cluster the jade door,

攢 (cuán), to cluster or stud. The jade door is close-set with gold nails, the way real palace gates were.

painted phoenixes dance at the cinnabar gate.

彩鳳舞朱門, painted phoenixes dancing at the cinnabar gate — the mirror of the studded jade door in the line before.

Galleried walks and winding corridors, everywhere intricate and translucent;

復道迴廊: double-decked walkways and looping corridors. 迴 is just the older way of writing 回.

triple eaves and fourfold brackets, tier upon tier where dragons and phoenixes wheel in flight.

三簷四簇, eaves tripled and brackets clustered — Chinese roof carpentry pushed past what carpentry can actually do. 翱翔 is soaring.

Above hangs a purple-towering, bright-flashing, perfectly round and gleaming great golden gourd-finial.

The tour closes on an 上面 / 下面 pair, above and below. Above sits the great golden 葫蘆頂, the gourd-shaped roof finial, buried under four doubled-up describing words — 紫巍巍, 明幌幌, 圓丟丟, 亮灼灼, purple-towering, bright-flashing, round-and-round, gleaming-gleaming. Chinese piles up repeated syllables where English reaches for adjectives, and the effect is closer to a drumroll. The whole run is kept as one unit.

Below stand sky-consorts holding aloft the fans, jade maidens bearing the immortal kerchiefs, fierce-glaring generals who marshal the court, high-spirited ministers who guard the throne.

And below, the staff: 天妃 holding the fans, 玉女 with the kerchiefs, generals glaring, ministers standing tall. That closes the pair.

At the very center:

正中間, "dead centre" — a short run-up to the last two treasures.

within a lapis dish are heaped, layer upon layer, the Pills of the Great One;

太乙丹, the pills of the Great One, Tàiyǐ — the highest elixir there is, piled in a dish like sweets. Heaven's way of showing off is to keep the priceless in bulk.

in an agate vase are set sprays of winding, twisting coral.

珊瑚樹, branching coral arranged like cut flowers in an agate vase. Elixir and coral close the catalogue.

Truly, every rare thing of the heavenly palace it holds,

Here is the clinch the whole poem has been walking towards: 般般有 against 件件無 — every kind of thing up here, not one of them down there.

while in the world below not one of them is found.

The second half of that contrast, and the poem's actual argument.

Gold towers and silver bell-carriages stand amid the purple courts,

金闕銀鑾, gold towers and silver bell-carriages. The poem now shifts into seven-syllable lines, 七言, and gathers the scene up in four matched couplets.

jasper flowers and jade grasses join the kingfisher blooms.

瓊葩, gem-blossoms — a last flourish of celestial gardening.

Past the altar's edge the Jade Hare goes paying court,

玉兔, the Jade Hare who pounds the elixir on the moon, and 金烏, the three-legged Golden Crow who is the sun. Moon and sun turn up to pay their respects like junior officials, which tells you the standing of the court they are reporting to.

skimming the depths below, the Golden Crow flies to attend the sage.

著底飛: 著 is zhuó here, "to keep close to, to graze," so the sun-crow flies low over the depths on its way in to the audience.

The Monkey King has the lot to come into this heavenly realm,

有分 (yǒu fèn) is "to have the lot, to be fated for." The poem stops describing and starts predicting: this place is owed to the monkey.

and falls not back into the human world's speck of filthy mud.

不墮 — the 不 shifting to bú before the falling tone of 墮 — "does not fall back" into 點污泥, the human world's "speck of filthy mud." A confident line. The chapter spends the rest of its length quietly taking it back.